By flickerdart on Imgur:
Titian
If the images have a dark background and everyone has tortured expressions on their faces, it’s Titian.
Peter Paul Rubens
If everyone in the paintings has enormous asses, then it’s Rubens.
Amerighi da Caravaggio
If all the men look like cow-eyed curly-haired women, it’s Caravaggio.
Pieter Bruegel
If the paintings have tons of little people in them but otherwise seem normal, it’s Bruegel.
Hieronymus Bosch
If the paintings have tons of little people in them but also have a ton of crazy bullshit, it’s Bosch.
Rembrandt van Rijn
If everyone looks like hobos illuminated only by a dim streetlamp, it’s Rembrandt.
François Boucher
If the painting could easily have a few chubby Cupids or sheep added (or already has them), it’s Boucher.
Michelangelo
If everyone is beautiful, naked, and stacked, it’s Michelangelo.
Edgar Degas
If you see a ballerina, it’s Degas.
El Greco
If everything is highly-contrasted and sharp, sort of bluish, and everyone has gaunt bearded faces, it’s El Greco.
Jan van Eyck
If everyone – including the women – looks like Putin, then it’s van Eyck.